| 摘要 |
PROBLEM TO BE SOLVED: To roll many kinds of channel steel which are the same series and have a fixed outside width and different thicknesses of web and flanges without forming a swelled part to a flange rolling equipment at both end parts of the web without exchanging rolling tools. SOLUTION: By executing reverse rolling of plural passes to a rough shape slab 17 using a 1st rough universal mill 12, edger mill 13 and 2nd rough universal mill 14, after executing thickness reduction of the web 17a, thickness reduction and edging of the flanges 17b and flattening reduction of the swelled part 20 where is formed by reduction with the 1st rough universal mill 12, the reverse rolling of one pass or plural passes is executed using the 2nd rough universal mill 14. Thus, edging of the flanges 17b is executed, also height reduction of the web 17a in accordance with the target thickness of the channel steel 32 is executed and, after that, the finish rolling of the web 17a and flanges 17b is executed using a finishing universal mill 15 having variable width horizontal rolls 30a, 30b whose width is on-line adjustable. |
